drm/radeon: 0x9649 is SUMO2 not SUMO

Fixes rendering corruption due to incorrect
gfx configuration.

bug:
https://bugs.freedesktop.org/show_bug.cgi?id=63599

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
1 file changed